One study finds some vegan protein products don't have significantly greener footprints than their meatier counterparts.

Yes, I realize most meat-eating Americans also create a lot of plastic waste, buying factory-farmed meat slabs encased in styrofoam and plastic wrap. But more eco-conscious non-vegetarians can get minimally packaged, locally grown meat and free-range organic eggs in reusable cartons at my farmers market. Such options, unfortunately, aren’t available for tofu eaters — unless they make their own tofu.

I still eat quite a lot of tofu — the locally made kind (though not from locally grown soybeans) available at Co-opportunity. But to reduce plastic waste, I’ve been eating more beans this year — which I can scoop into a reusable bag at the bulk section of my local co-op to make zero-waste, protein-rich meals.

This change has also made me more wary of overpackaged, overprocessed vegan fake meats.

Obviously, plastic packaging waste isn’t the only issue when it comes to food-related environmental concerns. In general, a vegan diet tends to have a lower carbon footprint — simply because factory-farmed beef has such an enormous carbon footprint. But that general statement definitely has its exceptions — meaning that how green a meat eater’s or vegan’s diet really is depends on what exactly that meat eater or vegan is chewing on.

In fact, Slate’s Green Lantern looked into how green tofu is compared to animal protein sources. Of course, tofu came out the green winner by far when compared to factory-farmed beef. But when compared to chicken and fish, vegetarian protein products didn’t always come out ahead:

Last year, the Dutch government commissioned a study of the environmental effects of vegetarian “meat substitutes,” including veggie burgers, Quorn and tofu. According to the analysis, a kilogram of tofu sold in the Netherlands produces about two kilograms of carbon-dioxide equivalent from the farm to the supermarket. That’s only a little less than Dutch chicken, at 3 kilograms of CO2-equivalent per kilogram of meat. Mackerel, herring, pollock and mussels — some of which the Lantern has already championed as low-carbon options for seafood lovers — scored about the same or better than tofu. That’s a much smaller difference than the Lantern would have expected.

Here’s a PDF of the English summary of the Dutch study, which is a pretty interesting read overall (Dairy products, for example, don’t score much better than meat — which is somewhat sad news for lacto-ovo vegetarians). Tofu sold in the Netherlands tends to come from South America though, so if I’m eating tofu made from soybeans grown in the U.S. then patted into tofu form locally, my protein would be greener. That said, if I’m instead eating processed fake meats — most of which are made in Taiwan then shipped here in plastic packaging — my vegan protein would likely be less green than the Dutch tofu. And if I compare that processed fake meat to, say, an organic egg from a neighbor’s backyard chicken, it seems pretty likely that the egg would win the green contest.

And of course, if I decided to down my fake meat meal with water-polluting soda and douse my dessert in mercury-tainted Hershey’s chocolate syrup, my meal would still be vegan but decidedly not green — or healthy.

All this is to say that while vegetarianism and veganism can usually help people move toward a much greener diet, it’s not necessarily always the greenest diet. Overprocessed, overpackaged foods just can’t be considered that green, even when they’re vegan.

I’m not urging everyone to give up their organic tofu. I still think it’s one of the greenest protein options out there, and I eat tofu myself practically every day. I’m just hoping we can have more productive, honest conversations about eco-friendly eating.

Whether vegan or carnivore or somewhere in between, what are you doing in 2010 to make your diet greener?